Multiple receiving arrangement



Jan. 1, 1935.

M. VON ARDENNE' 1,986,488

MULTIPLE RECEIVING ARRANGEMENT Filed May 10, 1930 2 Sheets-Sheet 1 /r7 van for:

WW uh Jan. 1, 1935.

M. VON ARDENNE 1,986,488

MULTIPLE RECEIVING ARRANGEMENT Filed May 10, 1930 2 Sheets-Sheet 2 hive/Won- Patented Jan. 1, 1935 cmrrn STATES;

PATENT oF-Fic a MULTIPLE RECEIVING ARRANGEMENT Manfredwon Ardenne, Berlin, Germany, assignor to RadioaktiengesellschaftD. S. Lowe, Berlin- Steg'litz, .Germanya company of Germany .fi-Applicaition- May 10, 1930, Serial No. 451,368 :Germany May 1'1, 1929 5 Claims. (crest-9) The invention relates to an arrangementfby According to-myinvention long distance recepv tion is made simultaneously for a greater number of local receiving" arrangements or other smallfsta tions having for instance only a detector tubeand' "lower frequency amplifying stages, bymeans of an aperiodichighfrequency amplifier WhiCh"fO1. lnSt3IIiCe may beset 'up as a'ceritralplant. Tire-mgr: frequency amplifying part of the receiving arrangement according to my invention SerJNo. 360,480 and consisting of some resistance-coupled double high frequency valves may be used in this connection. For this purpose a frame aerial, preferably also of an aperiodic nature-and an aperiodic high fre quency amplifier is used which latter may, for instance, consist of two or three high frequency multiple valves. The last system should in this connection, however, have other dimensions than In 'such an arrangement, however, the danger of reaction coupling is extremely great. It is avoided first by shielding of the frame aerial, secondly by suitably screening the high frequency amplifier and thirdly by close laying out the two leads to each receiver. They are laid parallel at a small distance which is covered by insulated bits. By way of comparison this has the effect of a bifilar wire connection.

In the arrangement according to the invention the aperiodic high frequency amplifier need not be provided with any selection elements. Since it is an aperiodic set, it will transmit a pretty wide frequency band and will even amplify the same. From this frequencyband the subscribers connected may at their direction select a number of distant stations and position them by means of their simple receivers whose fian e,- quire'd for a well operating long distance receiving set,is obviated; The problem of the house aerial, "which especially in densely populated i areas, could hardly be'solved at all, is'solved'in a means of selection sufiice if the frame aerial of the 'high frequency amplifier is appropriately v given the minimum direction of the local station. It is evident "that this method is of an extremely great, technically progressiveimpor- The great amount of expenditure resimple manner.

The invention will be more fully understood from the following detailed description and claims taken in connection with the accompany- 'ing drawings in which Fig. 1 shows diagramma tically an amplifier circuit embodying the invention and Fig. 2 shows a' similar circuit but with a cen'tralsource of operating potential. .In the drawings, 1 is a'frame aerial to be screened, 2 being the screen. This screen is earthed in a symmetric spot 3. 4 and 5 are the leads to the high frequency amplifier 6. In the screened arrangement 6 two high frequency multiple valves 26 and 36 are coupled by a resistance capacity coupling. The multiple valves, too, are containing such coupling elements. A further set of resistance capacity coupling elements is connected to the last high frequency amplifying system 7, thus giving a completely aperiodic high frequency amplifier.

This last system 7 which has an amplification factor of about 5 with a plate resistance 8 of about 500 ohms is more accurately shown in the figure. The internal resistance of this system shall be of the same order as the plate resistance. From anode 9 of the last system of the high frequency amplifier a number of leads 10, 11, 12 etc. branches off into which solid condensers 13, 14, 15 of about 200 cm. capacity have been inserted. In the drawings only the course of the leads 11 and 12 is followed up which with the zero potential lead 16 is conducted to two local station receivers 17 and 117 with the tuned circuits consisting of the self-inductions 18 and 118, variable capacities 19 and 119 and loudspeakers 20 and 120. In like manner the leads to all other local station receivers are joined up. One of these leads starts from the anode of the output system of the high frequency amplifier, whilst the other is the zero potential lead. The leads belonging together are, as has been mentioned above and as shown for the set 117, laid out at a small distance from one another. The first tubes of the receivers 17 and 117 may be a detector, both the other tubes are used for low frequency amplification.

According to the further object of the invention the operating voltages may also be supplied from central points, the apparatus serving the reception of the several subscribers thus being restricted to a minimum. The present invention gives means for a more extensive spread and improvement of broadcasting. It is, of course, possible too in this manner not only to provide the several subscribers connected with radio transmissions, but also to simplify to them the picture transmission and afterwards television.

Fig. 2 shows an arrangement, in which the receivers 17 and 117, and the high frequency amplifier, are supplied by a central source 21.

What I claim is:

1. In a receiving system for relaying distant signals over a distributing network supplying a plurality of local receivers, a central aperiodic high frequency amplifier, a power tube in the final stage of said amplifier, the amplification factor of said final tube being smaller than 5,

said final tube having a small internal resistance and a high anode current.

2. In a receiving system for relaying distant signals over a distributing network supplying a plurality of local receivers, a central aperiodic high frequency amplifier, a power tube in the final stage of said amplifier, the amplification factor of said final tube being smaller than 5, said final tube having a small'internal resistance and a high anode current, said final tube being connected with a plate resistance of about 500 ohms. l

3. In a receiving system for relaying distant signals over a distributing network supplying a plurality of local receivers, a central aperiodic high frequency amplifier, a power tube in the final stage of said amplifier, theamplification factor of said final tube being smaller than 5, said final tube having a small internalresistance and a high anode current, two leads "for conducting high frequency energy to the receivers which are held at a small distance from one another by insulating means, one of said leads being connected with the anode of the power tube of the high frequency amplifier by means of a constant. capacity of about 200 cm. to the grid end of the receiver circuit, the other one being zero potentialline to the cathode terminal of the receiver circuit.

4. In a receiving system for relaying distant signals over a distributing network supplying a .plurality of local receivers, a central aperiodic high frequency amplifier, a power tube in the final stage of said amplifier, the amplification factor of said final tube being smaller than 5,

said. final tube having a small internal resistance.

and a high anode current, for avoiding reaction coupling said central aperiodic high frequency amplifier being connected with a screened frame aerial.

"5'. 'In a receiving system for relaying distant signals over a distributing network supplying a 

